Mexico has scored a huge upset over world championship silver medallist Argentina with a 91-89 victory in the first game of the FIBA Americas Olympic basketball qualifying tournament in San Juan, Puerto Rico.

Mexico was very aggressive early in the game Wednesday, taking the early lead. Mexico led Argentina, 45-41, at halftime and extended that lead to 14 points in the middle of the third quarter. Argentina missed seemingly open shots throughout, but still pulled to within one point with less than a minute remaining. But Luis Scola missed an open shot from the top of the key with three seconds left and Mexico held on to win. Eduardo Najera led Mexico with 20 points, followed by Omar Quintero and Horacio Llamas with 13 each. Argentina's scoring was led by Scola and Andres Nocioni with 17 points each. In another opening game, the Dominican Republic edged Venezuela, 78-76.

The top three teams in the ten nation qualifying tournament earn berths to the Athens Olympics.